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Astro van cat conversion
- Thread starter Snowy Rivers
- Start date
Snowy Rivers
Well-known member
Yeah.....
I have not been into an engine since about 2010.....
Getting this 400 block back amongst the living is a lucky shot.
I was going to use the 305 that is currently in the chassis....(I needed something in the way of a small block Chevy with a common transmission to set up the Cat )
After thinking about how heavy this cat is (8000 LBS PLUS) I started thinking more about bigger power.
The biggest issue was size.....
I did not want to use one of the Ford 390 (FE Series ) that came in these cats....Been way too many years since this stuff was readily available used..
The Small block Chevy has been...and is.....so popular for projects ....Anything in the way of parts are easy to get...
These have been REINVENTED so many times and the aftermarket has met the need......
I did not want to do a stock 350....the stroker 383 stuff just gets spendy $$$$$ quick....
Then I remembered that the 1970's up through 1980 GM had produced the 400 small block...
I had a late 70's 4x4 pickup with one and it was OK....Nothing to write home about as far as power.....But in stock trim these were 8:1 Compression .....
Add some compression and a cam and they can be a beast..
Big plus.....Accessories from the mid/late 90's trucks all bolt on......
I ran an ad on Craig's list looking for a 400 block.
Was maybe a week and I got a call....Fella had one..
Sorry looking lot.....But standard bore.....
It was gonna be a lucky shot if the cylinders would clean up at .030" oversize.....IT DID....One cylinder had a slight dusting of rust at the bottom (Out of the ring travel) Just some little dark spots that look like a bit of pepper.....
That hole had been sitting with water in it for some time it seems ?????
The crank that came with the engine was a door stop.....RUSTY MESS
The heads on these engines were junk out of the box....HUGE 76cc chambers for the low compression......
Another rust pile......
But the old girl is going to life again......
Finding the nice (Like new) crank was a sweet treat...
Still need some parts....
Oil pump...pickup tube and bolt.....
Cam and timing set and a aftermarket timing cover to allow running the roller cam......
I am thinking about trying one of the one piece pan gaskets.....These look like a great deal....
This engine is a total piece together.. All the components are from various other engines....Crank I spoke of was from a factory short block......Heads are from a 1998 3500 Truck 350 engine....Pan is aftermarket as is the timing cover
Pistons are new Silvolite 1443 +030
Rocker arms are off the 1998 heads.....Rods came from another 400 engine..(Rod set the machine shop had in a box on the shelf)
Still need push rods for the valves...
I am still trying to decide on an intake manifold.....
Carburetor is very likely going to be a Holley off road truck Avenger 670 cfm
I saved all the bolts that fasten the Serpentine belt accessory brackets that came with the 1998 engine...
Head bolts off the 98 are still fine...
New pan bolt set
New Oil filter adapter kit
New Fuel pump rod and mounting plate....
New HEI Distributor
Late model exhaust manifolds
New flex plate
Flex plate bolts
There is more...I am sure of that
Just a "Coat of many colors"
It's Not the destination.....It's the journey on this one.....And an interesting one it has been.....
I have not been into an engine since about 2010.....
Getting this 400 block back amongst the living is a lucky shot.
I was going to use the 305 that is currently in the chassis....(I needed something in the way of a small block Chevy with a common transmission to set up the Cat )
After thinking about how heavy this cat is (8000 LBS PLUS) I started thinking more about bigger power.
The biggest issue was size.....
I did not want to use one of the Ford 390 (FE Series ) that came in these cats....Been way too many years since this stuff was readily available used..
The Small block Chevy has been...and is.....so popular for projects ....Anything in the way of parts are easy to get...
These have been REINVENTED so many times and the aftermarket has met the need......
I did not want to do a stock 350....the stroker 383 stuff just gets spendy $$$$$ quick....
Then I remembered that the 1970's up through 1980 GM had produced the 400 small block...
I had a late 70's 4x4 pickup with one and it was OK....Nothing to write home about as far as power.....But in stock trim these were 8:1 Compression .....
Add some compression and a cam and they can be a beast..
Big plus.....Accessories from the mid/late 90's trucks all bolt on......
I ran an ad on Craig's list looking for a 400 block.
Was maybe a week and I got a call....Fella had one..
Sorry looking lot.....But standard bore.....
It was gonna be a lucky shot if the cylinders would clean up at .030" oversize.....IT DID....One cylinder had a slight dusting of rust at the bottom (Out of the ring travel) Just some little dark spots that look like a bit of pepper.....
That hole had been sitting with water in it for some time it seems ?????
The crank that came with the engine was a door stop.....RUSTY MESS
The heads on these engines were junk out of the box....HUGE 76cc chambers for the low compression......
Another rust pile......
But the old girl is going to life again......
Finding the nice (Like new) crank was a sweet treat...
Still need some parts....
Oil pump...pickup tube and bolt.....
Cam and timing set and a aftermarket timing cover to allow running the roller cam......
I am thinking about trying one of the one piece pan gaskets.....These look like a great deal....
This engine is a total piece together.. All the components are from various other engines....Crank I spoke of was from a factory short block......Heads are from a 1998 3500 Truck 350 engine....Pan is aftermarket as is the timing cover
Pistons are new Silvolite 1443 +030
Rocker arms are off the 1998 heads.....Rods came from another 400 engine..(Rod set the machine shop had in a box on the shelf)
Still need push rods for the valves...
I am still trying to decide on an intake manifold.....
Carburetor is very likely going to be a Holley off road truck Avenger 670 cfm
I saved all the bolts that fasten the Serpentine belt accessory brackets that came with the 1998 engine...
Head bolts off the 98 are still fine...
New pan bolt set
New Oil filter adapter kit
New Fuel pump rod and mounting plate....
New HEI Distributor
Late model exhaust manifolds
New flex plate
Flex plate bolts
There is more...I am sure of that
Just a "Coat of many colors"
It's Not the destination.....It's the journey on this one.....And an interesting one it has been.....
Attachments
As far as carbs go I like the afb carter you can now buy new under the edelbrok name also gm used the quadra jet for so many years for a reason. one thing to think about is the new gas isnt blended for carbs now and i have a real problem with gas vapor in he cabin of my light foot im considering an efi conversion for just that reason.
Snowy Rivers
Well-known member
Good to know.....
My cab is well enough sealed being still pretty much as it was factory.....
I do like the Holley Off road avenger as they designed it so the vents do not dump fuel on steep up/down and sideways like the old street Holleys did and this stops flooding and such....
I was going to go with a Quadrajet.....But they are not really well suited for off road that much..
I had a K5 Blazer with a QJ on it.....It was OK...Buttttttttttttttttttttttt.....
I have gone to great lengths to stay away from stuff with diode boxes.....A carb will usually get you home.....When the electronics fail.....Game over....Long walk in the snow....//.Arrrrrgh
The only electronics that are serious on this build is the old school large cap HEI distributor......
I have used these for years in various rigs.....Yeah they can fail...But it is rare and can be repaired on the trail if need be with only a small handful of parts
My cab is well enough sealed being still pretty much as it was factory.....
I do like the Holley Off road avenger as they designed it so the vents do not dump fuel on steep up/down and sideways like the old street Holleys did and this stops flooding and such....
I was going to go with a Quadrajet.....But they are not really well suited for off road that much..
I had a K5 Blazer with a QJ on it.....It was OK...Buttttttttttttttttttttttt.....
I have gone to great lengths to stay away from stuff with diode boxes.....A carb will usually get you home.....When the electronics fail.....Game over....Long walk in the snow....//.Arrrrrgh
The only electronics that are serious on this build is the old school large cap HEI distributor......
I have used these for years in various rigs.....Yeah they can fail...But it is rare and can be repaired on the trail if need be with only a small handful of parts
Snowy Rivers
Well-known member
I got the Bore gauge and had time to try it out......
This little unit looks really good for the price ($80 to the door)
Is it a SUNNEN ....AHHHH....HELL NO.....
A Sunnen bore gauge is about $1200
We checked the new tool out against some known bearing bores (Large roller bearings laying on the shelf) and the results were spot on.......
The unit will measure from 1.4" to 6" bores
Nice plastic case.....
Be a great tool for the casual user ....home shop or hobby machinist
Stepping up for the $1200 Sunnen or other high end bore gauge is pretty much out of the question for most of us.
Ebay item "igaugingbrand"
After testing this unit against my top end MITUTOYO MICS......
If treated with respect.....One can get a lot of good use from this tool....
The bore on the Snow cat that needs to be checked....Engine rod bearing clearance....A walk in the park...
YOU MUST HAVE OD mics to set the gauge with.....
This $80 unit looks identical to the Mitutoyo 2" to 6" unit ....
I would be the Chinese made one is a direct copy....The layout of everything including the sticker on the handle looks the same...
Fit and finish of the Copy is very good......
This little unit looks really good for the price ($80 to the door)
Is it a SUNNEN ....AHHHH....HELL NO.....
A Sunnen bore gauge is about $1200
We checked the new tool out against some known bearing bores (Large roller bearings laying on the shelf) and the results were spot on.......
The unit will measure from 1.4" to 6" bores
Nice plastic case.....
Be a great tool for the casual user ....home shop or hobby machinist
Stepping up for the $1200 Sunnen or other high end bore gauge is pretty much out of the question for most of us.
Ebay item "igaugingbrand"
After testing this unit against my top end MITUTOYO MICS......
If treated with respect.....One can get a lot of good use from this tool....
The bore on the Snow cat that needs to be checked....Engine rod bearing clearance....A walk in the park...
YOU MUST HAVE OD mics to set the gauge with.....
This $80 unit looks identical to the Mitutoyo 2" to 6" unit ....
I would be the Chinese made one is a direct copy....The layout of everything including the sticker on the handle looks the same...
Fit and finish of the Copy is very good......
Attachments
Last edited:
Snowy Rivers
Well-known member
I ordered up the special oil pump pickup tube that works with the pan I got for the 406.
Ordered up a new performance oil pump too....Pump comes with the drive shaft, bolts to mount the pickup tube and a couple springs for adjusting the pressure...
Gotta sort out the Timing cover and that stuff.....
I want to try one of the one piece pan gaskets on this build....
Also going to sort out a remote oil filter mount with the cooler adapter set up as well..
Ordered up a new performance oil pump too....Pump comes with the drive shaft, bolts to mount the pickup tube and a couple springs for adjusting the pressure...
Gotta sort out the Timing cover and that stuff.....
I want to try one of the one piece pan gaskets on this build....
Also going to sort out a remote oil filter mount with the cooler adapter set up as well..
Snowy Rivers
Well-known member
Rainy weather is dampening my cat work.....Soooooooooooooooooo
Digging out goodies I bought quite a while back.....
Dug the new 6 quart oil pan out and getting it ready to go onto the new engine.
Trying to decide if the new "One piece oil pan gasket" is really worth the $$$$ compared to the 4 piece stuff we used for decades on small block Chevies........
I have never had a leak on a pan with the old school stuff.....Hard to really see any advantage.....
I am also not a fan of the one piece rear main seals either.....
The two piece silicone seals with the metal core rarely give issue.....
Now back in the day when we had the "Rope" seals.....Different story at times.
The new LS engines are notorious for rear main leaks.....Our 2005 Burb with the 5.3 is a real road oiler....
Quart every 2 weeks of just grocery getter driving...
Damned thing leave a puddle every time ya park it........
Not an easy job to replace either.....
Anyway.....THAT'S ANOTHER STORY....
Since the advent of the high temp RTV goop in the tube.....Stuff just does not leak.......
Ah well.......Pretty well made up my mind to go old school.....
Also discovered a fresh Large cap HEI distributor on the shelf too.......Left from another project that wen a slightly different direction.....
Added that to the pile of cat parts.....
Just need to get the cap and coil assembly..
I did not get an oil filter base with the 400 block.....Having the oil filter mounted remote is gonna be a plus.....That and the oil cooler .
I had spoken earlier of mounting the engine oil cooler up in the old core support area.....This still seems like a grand idea.....
May use an adapter that fits on the stock oil filter mount on the block and then connect the remote cooler and filter with good Aeroquip hose....
I can use the stock filter location for the test runs of the engine and then add the adapter after we are done with the breakin runs....
Getting at the filter down in the belly of the beast is just nasty.....Doable....But miserable.....messy too.....
My goal for the winter is to try and get the new engine complete and ready to test come spring.....Earlier if we can...
Still need a few parts......
I picked up a nice Chevy aluminum bell housing at a garage sale.....This will be a sweet addition to setting the engine up for testing.
I want to fab up a nice frame with casters so we can toll it in and out of the shop.....
Complete with a place for the battery, a control panel with a few gauges (Oil pressure and temp gauge) A fuel tank and electric pump..
Pretty much a complete test stand.....A small radiator might be nice.....May just go old school and connect the garden hose to the water pump inlet and run the outlet off to the ground.....
I might just bolt all the accessories on and go full bore top shelf .....
Be cool to have all the accessories on and operating during the test....Adding the radiator and fan would be sweet......
Will see what shakes......
I do have the Blazer radiator still sitting outside......Might check it out and see if it is suitable for the test stand....
I want to tun the engine for a few hours to break it in and allow any issues to show up.......
Digging out goodies I bought quite a while back.....
Dug the new 6 quart oil pan out and getting it ready to go onto the new engine.
Trying to decide if the new "One piece oil pan gasket" is really worth the $$$$ compared to the 4 piece stuff we used for decades on small block Chevies........
I have never had a leak on a pan with the old school stuff.....Hard to really see any advantage.....
I am also not a fan of the one piece rear main seals either.....
The two piece silicone seals with the metal core rarely give issue.....
Now back in the day when we had the "Rope" seals.....Different story at times.
The new LS engines are notorious for rear main leaks.....Our 2005 Burb with the 5.3 is a real road oiler....
Quart every 2 weeks of just grocery getter driving...
Damned thing leave a puddle every time ya park it........
Not an easy job to replace either.....
Anyway.....THAT'S ANOTHER STORY....
Since the advent of the high temp RTV goop in the tube.....Stuff just does not leak.......
Ah well.......Pretty well made up my mind to go old school.....
Also discovered a fresh Large cap HEI distributor on the shelf too.......Left from another project that wen a slightly different direction.....
Added that to the pile of cat parts.....
Just need to get the cap and coil assembly..
I did not get an oil filter base with the 400 block.....Having the oil filter mounted remote is gonna be a plus.....That and the oil cooler .
I had spoken earlier of mounting the engine oil cooler up in the old core support area.....This still seems like a grand idea.....
May use an adapter that fits on the stock oil filter mount on the block and then connect the remote cooler and filter with good Aeroquip hose....
I can use the stock filter location for the test runs of the engine and then add the adapter after we are done with the breakin runs....
Getting at the filter down in the belly of the beast is just nasty.....Doable....But miserable.....messy too.....
My goal for the winter is to try and get the new engine complete and ready to test come spring.....Earlier if we can...
Still need a few parts......
I picked up a nice Chevy aluminum bell housing at a garage sale.....This will be a sweet addition to setting the engine up for testing.
I want to fab up a nice frame with casters so we can toll it in and out of the shop.....
Complete with a place for the battery, a control panel with a few gauges (Oil pressure and temp gauge) A fuel tank and electric pump..
Pretty much a complete test stand.....A small radiator might be nice.....May just go old school and connect the garden hose to the water pump inlet and run the outlet off to the ground.....
I might just bolt all the accessories on and go full bore top shelf .....
Be cool to have all the accessories on and operating during the test....Adding the radiator and fan would be sweet......
Will see what shakes......
I do have the Blazer radiator still sitting outside......Might check it out and see if it is suitable for the test stand....
I want to tun the engine for a few hours to break it in and allow any issues to show up.......
Watch multi fit oil pans, I have a Milidon 8 quart pan on the power wagon, fits either LA or the magnum I put in it. I used the magnum 1 piece pan gasket, as the LA gaskets always leak. First time I drove it, I went up the hill then down the other side, when I hit the brakes it was a smoke show. Turns out that there is a relief in the front corners of the pan for the LA gaskets to lock into. The magnum gasket didn't seal it. I removed the pan, cleaned everything with Acetone and re assembled with RTV in the corners. No leaks since 2019.
Snowy Rivers
Well-known member
That stuff can happen.
The mopar stuff did do some odd things in there.....
I worked in a mopar shop in 1970/71 318, 340, 360, 383, 440 and a few Hemi rigs
Never got real deep into any mopars though
Small block Chevies..(Gen 1) are all the same.
About 1958 to 1987....When they started updating things. (1990) and the one piece rear main
Two piece rear main seal and these are all pretty much a no brainer (My engine block is a late 1980) OLD SCHOOL STUFF
The one piece pan gaskets are made for these....But the extra $$$$$$$$$$$ as compared to the original stuff....I can't see a real benefit....I have never had a leaker....
Ordered more goodies this morning
Ordered up a GM factory oil filter adapter with bypass (What the engine came with) Kit comes with the gasket too.
Just need a couple bolts.
Also ordered up a remote filer/cooler adapter that fastens on where the filter normally goes.
Uses AN fittings and Aeroquip hose to connect to filter and cooler.....
Figured we might as well get this stuff on hand.....I can figure out where the filter can go and make the hoses up to work...
We can do a temporary mount on the test stand and not have to mess with whats on the engine from then on...
The cats came with oil coolers...At least the 2100 had one....What was left of mine was not worth much.
An electric fan type cooler mounted high up in the old core support on the LH side will be sweet.
I do not have enough room in the regular cooling stack to get anything in there...
The tranny cooler will go on the opposite side of the core support..........
A bit of hoses to deal with.
The Aeroquip field serviceable fittings and hose are the Catsass....Easy to work with and very durable...
Simple hand tools is all ya need.....Use a cutoff wheel on the die grinder to cut the hose....Wash out and blow dry...Good to go.
The mopar stuff did do some odd things in there.....
I worked in a mopar shop in 1970/71 318, 340, 360, 383, 440 and a few Hemi rigs
Never got real deep into any mopars though
Small block Chevies..(Gen 1) are all the same.
About 1958 to 1987....When they started updating things. (1990) and the one piece rear main
Two piece rear main seal and these are all pretty much a no brainer (My engine block is a late 1980) OLD SCHOOL STUFF
The one piece pan gaskets are made for these....But the extra $$$$$$$$$$$ as compared to the original stuff....I can't see a real benefit....I have never had a leaker....
Ordered more goodies this morning
Ordered up a GM factory oil filter adapter with bypass (What the engine came with) Kit comes with the gasket too.
Just need a couple bolts.
Also ordered up a remote filer/cooler adapter that fastens on where the filter normally goes.
Uses AN fittings and Aeroquip hose to connect to filter and cooler.....
Figured we might as well get this stuff on hand.....I can figure out where the filter can go and make the hoses up to work...
We can do a temporary mount on the test stand and not have to mess with whats on the engine from then on...
The cats came with oil coolers...At least the 2100 had one....What was left of mine was not worth much.
An electric fan type cooler mounted high up in the old core support on the LH side will be sweet.
I do not have enough room in the regular cooling stack to get anything in there...
The tranny cooler will go on the opposite side of the core support..........
A bit of hoses to deal with.
The Aeroquip field serviceable fittings and hose are the Catsass....Easy to work with and very durable...
Simple hand tools is all ya need.....Use a cutoff wheel on the die grinder to cut the hose....Wash out and blow dry...Good to go.
Thefatsquatch
Active member
Hey I am putting a jib-crane on the Thiokol this year, just because the tracks are so damn heavy. If you need to pop your tracks off and throw them in the truck, we can put them back on over there!
Snowy Rivers
Well-known member
Sweeeeeeet.
Well ...Truth be known.....Kitty will not be ready this season.
I am getting right along with the engine.
Still a lot of work to do.....
Thank you so much for the heads up.....
Well ...Truth be known.....Kitty will not be ready this season.
I am getting right along with the engine.
Still a lot of work to do.....
Thank you so much for the heads up.....
Snowy Rivers
Well-known member
Goodies for the engine are slowly trickling in...
Oil filter adapter/bypass (Factory Delco part) showed up.....Just got the adapter to relocate the filter from under the engine to a spot out front where it is accessible....Also allows a cooler to be plumbed into the system......
Ordered the Cloyes (Quick button) aluminum timing cover....
Needed this to easily add a thrust button to the cam shaft......Roller cams have straight lobes and without a thrust plate or a button will shift fore and aft....Flat tappet cams are ground so there is a slight angle to the lifters to keep the cam in place with the thrust surface of the top sprocket touching the engine block) Later Small block engines (86 and up) saw the roller cam introduced.......There is a plate on the front of the cam bearing bore that keeps the cam secure.
Early GEN 1 engines need a button to stop the cam from moving.
The stock sheet metal timing cover is too flimsy....and it is hard to get the clearance correct.....
The Cloyes is a two piece unit with an adjustable arrangement to get things just right and do it reliably .....
The roller cam in the older blocks also requires that the lifters have a "Tie Bar" between the pairs.....Factory set up uses a "Dog bone" the keeps the lifters aligned and a sheet metal "Spider" to hold the dog bones in place.
I have seen a few guys retrofit the factory system.....It requires drilling and tapping holes into the upper oil gallery and adding threaded studs to secure the spider......The dog bones do not lay perfect on top of the lifters.....The factory roller blocks are designed so these parts all fit ......CAN A GOOD RETRO BE DONE....YES IT CAN....JUST A BIG PAIN IN THE AZZ......Needs to be done with the block bare and be able to get the block in the mill to take a light cut on the lifter bore bosses so the dog bones lay flat and square........
This requires care in cleaning out the oil passage of metal after machining......The dog bones may also need a bit of massaging to clear the block as well.......Pretty HINKY at best in my opinion.....The tie bar lifters are easier and do not require any machining "Plug and Play"
To get all the "Trick stuff" would really be best using an after market big bore block......$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ Not for this build.....
I was still thinking about going with a flat tappet cam....Sadly the lifter manufactures have all but quit making flat tappet lifters.....Too much stuff coming in from overseas....AND IT IS JUNK.....The cams made by the major mfg's are good...Just way too many failures due to junk lifters....Plus the new oils will not sustain a flat tappet cam....
There are special "Racing oils" available that are as good as oils ever were.....But availability is an issue and cost too....
Ya can't just grab a few quarts at Autozone or Napa and go....
These are a few "Classic car oils" out there....But even these have come into question of late......
The choice for a cam comes full circle back to a roller........
And so the goodies keep on coming...The fact that I needed a timing cover anyway made this one an easy choice.....
Ordered up a "Crank turning tool" This slips onto the crank to allow turning the engine forward and backwards without loosening the crank bolt.
Also has a knurled nut to allow a degree wheel to slip on and be snugged up.
We can degree in the cam and also check the TDC mark on the dampener.
Degreeing in the cam is a must do with any performance cam.....I did not do it one time....And the engine ran like crap.
Cam was off a bunch.......Had to go back and degree things to find that the dowel pin was off.....The cam company replaced the cam......A lot of work wasted......
Not again......
I have the degree wheel.....But the adapter turning tool makes things far easier to get the wheel spot on.....
I used to have a "Positive stop" tool to find TDC.......Can't find it.....Will need to make a new one.
The sheet metal timing tabs on many engines are OFF......Sometimes a lot....
Real easy to do the check and see wasssssup before trying to degree the cam......
I also want to check PISTON TO VALVE CLEARANCE"
Use a pair of solid lifters and adjust to zero clearance.....With a strip of kids modeling clay on the piston top.....Roll the engine through a few times and then take the head off......cut the clay and measure the thickness......
With the mixing and matching of pistons, cam shaft and heads that are way different from stock.....We need to be sure we are not gonna have a train wreck.
The pistons have a fair dish in them.....The cam has a lot more lift than stock ....And the Vortec heads are a bunch different .
I am pretty sure we are fine.....BUT WE ARE GONNA CHECK THIS ANYWAY.....
Hitting the valves with a piston is just UGLY
I have used a couple different performance cams in the 400 sbc (Stock) and never hit any pistons.
The Vortec heads and a bit more lift in the cam on this build are significant outliers ....Just gonna do it.....
Oil filter adapter/bypass (Factory Delco part) showed up.....Just got the adapter to relocate the filter from under the engine to a spot out front where it is accessible....Also allows a cooler to be plumbed into the system......
Ordered the Cloyes (Quick button) aluminum timing cover....
Needed this to easily add a thrust button to the cam shaft......Roller cams have straight lobes and without a thrust plate or a button will shift fore and aft....Flat tappet cams are ground so there is a slight angle to the lifters to keep the cam in place with the thrust surface of the top sprocket touching the engine block) Later Small block engines (86 and up) saw the roller cam introduced.......There is a plate on the front of the cam bearing bore that keeps the cam secure.
Early GEN 1 engines need a button to stop the cam from moving.
The stock sheet metal timing cover is too flimsy....and it is hard to get the clearance correct.....
The Cloyes is a two piece unit with an adjustable arrangement to get things just right and do it reliably .....
The roller cam in the older blocks also requires that the lifters have a "Tie Bar" between the pairs.....Factory set up uses a "Dog bone" the keeps the lifters aligned and a sheet metal "Spider" to hold the dog bones in place.
I have seen a few guys retrofit the factory system.....It requires drilling and tapping holes into the upper oil gallery and adding threaded studs to secure the spider......The dog bones do not lay perfect on top of the lifters.....The factory roller blocks are designed so these parts all fit ......CAN A GOOD RETRO BE DONE....YES IT CAN....JUST A BIG PAIN IN THE AZZ......Needs to be done with the block bare and be able to get the block in the mill to take a light cut on the lifter bore bosses so the dog bones lay flat and square........
This requires care in cleaning out the oil passage of metal after machining......The dog bones may also need a bit of massaging to clear the block as well.......Pretty HINKY at best in my opinion.....The tie bar lifters are easier and do not require any machining "Plug and Play"
To get all the "Trick stuff" would really be best using an after market big bore block......$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ Not for this build.....
I was still thinking about going with a flat tappet cam....Sadly the lifter manufactures have all but quit making flat tappet lifters.....Too much stuff coming in from overseas....AND IT IS JUNK.....The cams made by the major mfg's are good...Just way too many failures due to junk lifters....Plus the new oils will not sustain a flat tappet cam....
There are special "Racing oils" available that are as good as oils ever were.....But availability is an issue and cost too....
Ya can't just grab a few quarts at Autozone or Napa and go....
These are a few "Classic car oils" out there....But even these have come into question of late......
The choice for a cam comes full circle back to a roller........
And so the goodies keep on coming...The fact that I needed a timing cover anyway made this one an easy choice.....
Ordered up a "Crank turning tool" This slips onto the crank to allow turning the engine forward and backwards without loosening the crank bolt.
Also has a knurled nut to allow a degree wheel to slip on and be snugged up.
We can degree in the cam and also check the TDC mark on the dampener.
Degreeing in the cam is a must do with any performance cam.....I did not do it one time....And the engine ran like crap.
Cam was off a bunch.......Had to go back and degree things to find that the dowel pin was off.....The cam company replaced the cam......A lot of work wasted......
Not again......
I have the degree wheel.....But the adapter turning tool makes things far easier to get the wheel spot on.....
I used to have a "Positive stop" tool to find TDC.......Can't find it.....Will need to make a new one.
The sheet metal timing tabs on many engines are OFF......Sometimes a lot....
Real easy to do the check and see wasssssup before trying to degree the cam......
I also want to check PISTON TO VALVE CLEARANCE"
Use a pair of solid lifters and adjust to zero clearance.....With a strip of kids modeling clay on the piston top.....Roll the engine through a few times and then take the head off......cut the clay and measure the thickness......
With the mixing and matching of pistons, cam shaft and heads that are way different from stock.....We need to be sure we are not gonna have a train wreck.
The pistons have a fair dish in them.....The cam has a lot more lift than stock ....And the Vortec heads are a bunch different .
I am pretty sure we are fine.....BUT WE ARE GONNA CHECK THIS ANYWAY.....
Hitting the valves with a piston is just UGLY
I have used a couple different performance cams in the 400 sbc (Stock) and never hit any pistons.
The Vortec heads and a bit more lift in the cam on this build are significant outliers ....Just gonna do it.....
Snowy Rivers
Well-known member
A piccy of some of the new parts....I need to pick up the filter adapter (Bolts to block) at the post office.
I spent time gathering good hard data on the engine parts.
Piston dish.................................... 20cc
Piston in the hole.......................... .010"
Gasket thickness compressed....... .038"
Gasket volume and diameter (Calculator figures the thickness and diameter)
Bore size ...................................... 4.155"
Stroke........................................... 3.750"
Vortec head chamber size ........... 64cc
Being a bit more accurate is far better at getting a good accurate number
We are in the area of ................... 9.7:1
This should really wake up the 406 cubes
The factory 400 with stock bore and the 78cc heads was at 8.5:1
They were good on torque....but overall a turd...Considering 400 inches should do something.......
The Vortec heads with a much better cam and a touch more comp. than the L31 they came with...Plus 56 more cubes gonna do something me thinks....
L31 350 had 9.4:1:1 comp........
I am real pleased with the numbers.....
Gonna be exciting to see how the little beast runs
I spent time gathering good hard data on the engine parts.
Piston dish.................................... 20cc
Piston in the hole.......................... .010"
Gasket thickness compressed....... .038"
Gasket volume and diameter (Calculator figures the thickness and diameter)
Bore size ...................................... 4.155"
Stroke........................................... 3.750"
Vortec head chamber size ........... 64cc
Being a bit more accurate is far better at getting a good accurate number
We are in the area of ................... 9.7:1
This should really wake up the 406 cubes
The factory 400 with stock bore and the 78cc heads was at 8.5:1
They were good on torque....but overall a turd...Considering 400 inches should do something.......
The Vortec heads with a much better cam and a touch more comp. than the L31 they came with...Plus 56 more cubes gonna do something me thinks....
L31 350 had 9.4:1:1 comp........
I am real pleased with the numbers.....
Gonna be exciting to see how the little beast runs
Attachments
Take into consideration the cam profile, static CR is one thing an dynamic CR is another. Tight Lobe centers and short duration can build a lot of cylinder pressure down low.
Snowy Rivers
Well-known member
Yes it can.....
Dynamic ratio is far more telling of the real deal.....
Cam that's going in is a Marine cam
Comp cams Extreme Marine (XM270HR-12)
Duration @.050" Int 218....Exh 224
Lift Int .495" Exh .503"
LSA 112 Degrees
This is a great boat cam.....Snow cat is more like a boat with long periods of high RPM Vs the type of running on a car/truck.
I wanted to keep the lift reasonable...The Vortec heads flow best at about .500" The Vortec was designed for a medium .400" lift cam....Split duration with exhaust a tad longer....Lift slightly higher on the Exh side...
The marine cams are designed to deal with wet exhaust and not suck in water....Not an issue here....Comp says the marine cam is a great choice for an engine running at a stead higher RPM
Here is a link to a 5.7 SBC with this cam.....The extra cubes in my engine may cover some of the lumpy idle....But it will still have the great mid range.....We do not need anything much above 4500 RPM
This cat gonna sound great....2-1/2" dual pipes with Super 10 mufflers ....Last 2 feet or so of the exhaust transitions to 4"
Here is a set of super 10 on a camaro...
The cam will work fine with a stock converter.....Not much different than the drag of a good sized prop on a Mercruiser at idle...
A very lovely
"CHOP" to the idle..... KENTUCKY..KENTUCKY..KENTUCKY..KENTUCKY......
The 4" boom tubes on the back will make this sound just BADAZZ...
1500 TO 5500 RPM
1500 is about 5 mph in 3rd gear.....The gears in the cat will easily allow this cam to get on the step real quick......
4500 is about 15 mph in 3rd gear.....
These are hard numbers based on zero slip.....Sprockets turn the track 48" per revolution
I have no idea just how this thing will handle at 15 mph
I have driven a stock 2100 at full speed at the rated 12.4 mph published by Thiokol.
Spoooooooooooooky.....
But the numbers are just that...numbers on a page....Getting the feel of it and seeing how much BUTT PUCKER occurs and at what speed will tell the real story...
This engine can easily handle 5000 rpm. (17 mph)
Likely approaching insanity ......
We will play that game out when we get there...
Dynamic ratio is far more telling of the real deal.....
Cam that's going in is a Marine cam
Comp cams Extreme Marine (XM270HR-12)
Duration @.050" Int 218....Exh 224
Lift Int .495" Exh .503"
LSA 112 Degrees
This is a great boat cam.....Snow cat is more like a boat with long periods of high RPM Vs the type of running on a car/truck.
I wanted to keep the lift reasonable...The Vortec heads flow best at about .500" The Vortec was designed for a medium .400" lift cam....Split duration with exhaust a tad longer....Lift slightly higher on the Exh side...
The marine cams are designed to deal with wet exhaust and not suck in water....Not an issue here....Comp says the marine cam is a great choice for an engine running at a stead higher RPM
Here is a link to a 5.7 SBC with this cam.....The extra cubes in my engine may cover some of the lumpy idle....But it will still have the great mid range.....We do not need anything much above 4500 RPM
This cat gonna sound great....2-1/2" dual pipes with Super 10 mufflers ....Last 2 feet or so of the exhaust transitions to 4"
Here is a set of super 10 on a camaro...
The cam will work fine with a stock converter.....Not much different than the drag of a good sized prop on a Mercruiser at idle...
A very lovely
"CHOP" to the idle..... KENTUCKY..KENTUCKY..KENTUCKY..KENTUCKY......
The 4" boom tubes on the back will make this sound just BADAZZ...
1500 TO 5500 RPM
1500 is about 5 mph in 3rd gear.....The gears in the cat will easily allow this cam to get on the step real quick......
4500 is about 15 mph in 3rd gear.....
These are hard numbers based on zero slip.....Sprockets turn the track 48" per revolution
I have no idea just how this thing will handle at 15 mph
I have driven a stock 2100 at full speed at the rated 12.4 mph published by Thiokol.
Spoooooooooooooky.....
But the numbers are just that...numbers on a page....Getting the feel of it and seeing how much BUTT PUCKER occurs and at what speed will tell the real story...
This engine can easily handle 5000 rpm. (17 mph)
Likely approaching insanity ......
We will play that game out when we get there...
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Snowy Rivers
Well-known member
BOAT DIESELS ARE FINE....
A lot of pleasure craft are powered with gasoline engines.
I agree...UP HILL ALL THE TIME....NO COAST
A snow cat may have a little lightening of the load at times...But more like a boat....Especially like the long time operating at high RPM.
Some of the 3700 LMC cats used 3208 diesels....Among other engines.....
Ah well....We gonna make do with what we got.
I think most currently manufactured snow cats are diesel powered.....
A lot of pleasure craft are powered with gasoline engines.
I agree...UP HILL ALL THE TIME....NO COAST
A snow cat may have a little lightening of the load at times...But more like a boat....Especially like the long time operating at high RPM.
Some of the 3700 LMC cats used 3208 diesels....Among other engines.....
Ah well....We gonna make do with what we got.
I think most currently manufactured snow cats are diesel powered.....
Snowy Rivers
Well-known member
I got the factory oil filter adapter yesterday.
A lot of Bad info spread on the net about this part.....Use a gasket....Don't use a gasket.
All my GM shop manuals show the gasket.....
The noise about the gasket was "It will come apart and clog an oil passage"
I have never seen a SBC without a gasket.....
The part I got (OEM) has a gasket that is a thin steel core with a polymer coating on each side.
The adapter has a thin little ridge around the face where it contacts the block that presses into the gasket..
Some of the after market gaskets are a stiff paper type.....These might fail....I can't say.....But going with the OEM part....Gotta be a good plan.
A lot of Bad info spread on the net about this part.....Use a gasket....Don't use a gasket.
All my GM shop manuals show the gasket.....
The noise about the gasket was "It will come apart and clog an oil passage"
I have never seen a SBC without a gasket.....
The part I got (OEM) has a gasket that is a thin steel core with a polymer coating on each side.
The adapter has a thin little ridge around the face where it contacts the block that presses into the gasket..
Some of the after market gaskets are a stiff paper type.....These might fail....I can't say.....But going with the OEM part....Gotta be a good plan.
Attachments
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To tell the truth the 603 I had, the 250CI ford six was plenty and actually could have gotten by as a commuter rig with a lot less, Nixon put a 4 cylinder diesel in a Tucker with excellent results. A cummins 4bt turned up slightly would make more power than a stock big chevy and would get miles to the gallon instead of gallons to the mile. That Thiokol 603 I had with the six would burn 20 gallons going 15 miles, thats one reason I sold it and built the mini track van. Im getting ready to put a slightly turned up cummins b3.3 in a 1970 dodge pickup. At 3500# with a 700r4 comparable builds are reporting a combined 38 mpg. The 3.3 turned up a little makes 150hp and 400 tq, with the hp@ 2900 and the tq @ 1600 rpm. makes more power than the small block in it now. I also know you already got everything and you are committed to that as it would blow things up too much on your build. When you started it gas was $ 2.30 a gallon and now it $7.00 depending on where you live.
Snowy Rivers
Well-known member
Cool stuff.....The Ford 6 cyl is a good engine....
The Torque on the little Cummins 4 cyl is really good too.....
The reasoning behind my choice on a power pack (Engine and tranny) were several.
Physical size to fit in the chassis tub...
Weight......I did not want an 800 plus pound engine and then have to add a big azz tranny to hold onto it
Availability of the engine and parts readily and affordably....
After market goodies to allow ease of adaptation to the chassis
A complete accessory package that was a bolt on plug and play (Alternator, steering pump, water pump,fan and such)
The small block chevy just jumps off the page and stands out.
Ease of getting parts....
Tons of aftermarket parts to adapt the engine....(Mounting hardware, exhaust manifolds ...huge variety out there )
Performance goodies that allow just about any dream to work well...
Good choice of tranny's....I chose the TH350...Reliable, sturdy and low cost to build....A TH400 could have worked...A little long for what I wanted...
The reason for my choosing the 400 Small block.....BECAUSE I wanted something a bit different.....
The long stroke of the 400 builds much more torque and can do it lower in the RPM range..
Every hot dog wants a 383 chevy small block.....Waaaaaaay too $$$$$$$$$$$
The 400 was literally dirt cheap......The 1998 Vortec heads are about the best heads available unless the budget is bottomless......
I can sit here at my terminal and scare up anything I need for the little mouse motor at affordable prices
Parts are easy to find too...
I originally gave diesel a good look.....
I looked at the 6.2 GM.....Plenty of power....Too heavy, too wide
I considered a couple other options...The parts availability was not that good.....The Cummins is a great engine....Not that easy to find.
The demand for the 4BT is high......
Even though my engine is a MUTT ...It is still a small block chevy with all chevy accessories ....So many choices of stuff that bolt right on....
Just seemed like a good plan....
I the past when big inch chevies were scarce...(454) and spendy to get hold of.... I adapter a 455 olds in a truck I had...
The big Olds was a real torque monster......Not a screamer....Just a stump puller
Best part....The stuff will fit in a Chevy pickup easily....
And so it goes.....
The Torque on the little Cummins 4 cyl is really good too.....
The reasoning behind my choice on a power pack (Engine and tranny) were several.
Physical size to fit in the chassis tub...
Weight......I did not want an 800 plus pound engine and then have to add a big azz tranny to hold onto it
Availability of the engine and parts readily and affordably....
After market goodies to allow ease of adaptation to the chassis
A complete accessory package that was a bolt on plug and play (Alternator, steering pump, water pump,fan and such)
The small block chevy just jumps off the page and stands out.
Ease of getting parts....
Tons of aftermarket parts to adapt the engine....(Mounting hardware, exhaust manifolds ...huge variety out there )
Performance goodies that allow just about any dream to work well...
Good choice of tranny's....I chose the TH350...Reliable, sturdy and low cost to build....A TH400 could have worked...A little long for what I wanted...
The reason for my choosing the 400 Small block.....BECAUSE I wanted something a bit different.....
The long stroke of the 400 builds much more torque and can do it lower in the RPM range..
Every hot dog wants a 383 chevy small block.....Waaaaaaay too $$$$$$$$$$$
The 400 was literally dirt cheap......The 1998 Vortec heads are about the best heads available unless the budget is bottomless......
I can sit here at my terminal and scare up anything I need for the little mouse motor at affordable prices
Parts are easy to find too...
I originally gave diesel a good look.....
I looked at the 6.2 GM.....Plenty of power....Too heavy, too wide
I considered a couple other options...The parts availability was not that good.....The Cummins is a great engine....Not that easy to find.
The demand for the 4BT is high......
Even though my engine is a MUTT ...It is still a small block chevy with all chevy accessories ....So many choices of stuff that bolt right on....
Just seemed like a good plan....
I the past when big inch chevies were scarce...(454) and spendy to get hold of.... I adapter a 455 olds in a truck I had...
The big Olds was a real torque monster......Not a screamer....Just a stump puller
Best part....The stuff will fit in a Chevy pickup easily....
And so it goes.....
Snowy Rivers
Well-known member
The 4 BT is a sweet engine....For what they were used for.....Perfect.....
For my application the size and weight is a killer
4BT ...............750#
Chevy 400 SB 575#
The size...While the Cummins is fairly compact it is wider than the Chevy....Likely due to the location of the injection pump assembly.
The 2100 Thiokol is so narrow in the tub that it makes fitting a V8 down in the tub a challenge....
The Ford 391 (Factory in the 2100) was mounted quite a bit higher than where my Chevy 406 is...
The top edges of the tub are splayed out quite a bit to allow the engine to fit
The 3700 cat was available with a 3208 Cat,,,,,Even larger and heavier (Much heavier at 1800#)
But 636 cubes and gobs of torque (Up to 375 HP/800 Lb of torque)
All in all ...I wanted the engine to be a tad lighter and lower than factory......Being set forward as it is the weight is quite a bit in front of the front axle.......
A tucker (Older machines) has the engine more centered over the front axle....The later mid engine diesels are a lot different as far as weight distribution.
The $3700 price on the 4BT albeit not huge ....Is a pretty big step up from the cost of my completed 406....Probably twice as much.
I am not real sure why Thiokol designed the 2100 and 3700 the way they did....But the design seemed to work OK
The wanted the cab to be in the center to give the operator a better ride.....(Less up and down when navigating rough terrain....
The cab forward like the Pisten Bully gives the operator a great view of the blade and what it is doing.....
Ah well.....Ideas are many...for sure.....
For my application the size and weight is a killer
4BT ...............750#
Chevy 400 SB 575#
The size...While the Cummins is fairly compact it is wider than the Chevy....Likely due to the location of the injection pump assembly.
The 2100 Thiokol is so narrow in the tub that it makes fitting a V8 down in the tub a challenge....
The Ford 391 (Factory in the 2100) was mounted quite a bit higher than where my Chevy 406 is...
The top edges of the tub are splayed out quite a bit to allow the engine to fit
The 3700 cat was available with a 3208 Cat,,,,,Even larger and heavier (Much heavier at 1800#)
But 636 cubes and gobs of torque (Up to 375 HP/800 Lb of torque)
All in all ...I wanted the engine to be a tad lighter and lower than factory......Being set forward as it is the weight is quite a bit in front of the front axle.......
A tucker (Older machines) has the engine more centered over the front axle....The later mid engine diesels are a lot different as far as weight distribution.
The $3700 price on the 4BT albeit not huge ....Is a pretty big step up from the cost of my completed 406....Probably twice as much.
I am not real sure why Thiokol designed the 2100 and 3700 the way they did....But the design seemed to work OK
The wanted the cab to be in the center to give the operator a better ride.....(Less up and down when navigating rough terrain....
The cab forward like the Pisten Bully gives the operator a great view of the blade and what it is doing.....
Ah well.....Ideas are many...for sure.....
The 4bt weighs 200# more than your small block, the $3700.00 price includes the transmission, intercooler and radiator. Not saying you should change direction, as you already have everything, just sharing the info for something in the future, like a truck re power.
Snowy Rivers
Well-known member
Thanks for the tip...
There is a local shop here in town that has done several 4BT conversions.....IIRC they did one in a Toyota LC (Older style)
That rig was a body off frame rebuild with different Axles, T case, transmission and GAWD knows what all else
A severe duty FJ40 1970's vintage
Turned out sweet.....But a spendy project.
Well I figure the cat is my last project ....At 71 and in failing health.....It's time to pass the torch....
Back in the early 80's I did a 3208 cat in the FORD F350 4x4.....Conversion.....Helluva project
After sitting the Cat engine in...We had to pick the front end off the dirt.
Put a 4 speed Allison tranny in the beast....Fella was hauling a big gooseneck trailer......The V8 kitty cat did a good job....
IIRC it was a 250 HP ....Gobs of torque.
There is a local shop here in town that has done several 4BT conversions.....IIRC they did one in a Toyota LC (Older style)
That rig was a body off frame rebuild with different Axles, T case, transmission and GAWD knows what all else
A severe duty FJ40 1970's vintage
Turned out sweet.....But a spendy project.
Well I figure the cat is my last project ....At 71 and in failing health.....It's time to pass the torch....
Back in the early 80's I did a 3208 cat in the FORD F350 4x4.....Conversion.....Helluva project
After sitting the Cat engine in...We had to pick the front end off the dirt.
Put a 4 speed Allison tranny in the beast....Fella was hauling a big gooseneck trailer......The V8 kitty cat did a good job....
IIRC it was a 250 HP ....Gobs of torque.
Another option is the cummins 3.3 they weigh 575# come in wood chippers etc. can easily make 150 hp and 400 tq, in a FJ they have more power than the original power plant and get in the high 30's for combined mileage. I got one that needs freshening for $1000.00 and plan to put it in a 1970 Dodge pickup I have along with a 700r4. @3500# its about the same weight as the FJ so I should realize similar results. It will be a full sized 1/2 ton truck with small block power that gets mpg in the high 30's. Like you I am getting long in the tooth but will have more time for projects in another year and a half when I retire. Also been gathering parts to to body swap a 1969 power wagon onto a 1998 Dodge 3500 chassis with a p pumped 24 valve. Im done hijacking your post
Snowy Rivers
Well-known member
I know it is not polite to "Toss cold water on someones campfire"
The 700R4 trans is a pretty weak gearbox.....Even the later versions the 4L60E with all the updates and redesigns are still sketchy....
I was in the Auto tranny Bizz for many years and the 700R4 was what paid the bills for us...
They are fine in very light rigs.....Medium sized sedans and small vans.....GM installed them in 1/2 ton pickups and they installed them in the K5 Blazer 4x4 behind the 6.2 Diesel.
The internals are small and way too light for any hard use.....
The later 700R4 right before they renamed them and went electronic were the best of the crop.
The updates, service bulletins and other paperwork from GM was staggering during the early years.
A shelf 8' long stacked like a book shelf was what was needed to hold all the service bulletins and updates...
Yessss...The aftermarket has really stepped up to the bar and fixed a lot of the issues....Still, the components are tiny and you can only do so much with small parts..
IMHO I would use a TH400 BOX and a gear vendors OD behind that......If the rig is a 4x4 it gets a bit tougher to make stuff work due to the space required.
None of the Auto makers made/make a really good tranny... ( Overdrive boxes)
The TH 350 was pretty decent and with a shift kit was good.
The TH 400 was "Nearly bomb proof"
The Ford C6 was a stout box...Again a shift kit was needed to really make them top shelf
The Mopar 727 in stock trim was pretty lame....Shgift kits and a few goodies would get them up to par
Many customers would bitch after we put in a shift kit because of the firm shifts.....
The late Mopar stuff like the 48RFE and 68RFE keep many tranny shops in business....
My son in law has had the tranny in his 08 Dodge 6.7 rebuilt twice now and the cost is staggering.....
Every auto maker wants to brag about their BIG AZZ DIESEL ...But they never think much about the tranny..
The Allison is fairly decent.....Better than the Dodge boxes by light years.
Still I cringe when I think about the power that so many folks are trying to shove at these poor tranny's.....
The older Allison 4 speed boxes are good.....But for most applications they have way too much parasitic drag internally..
A good choice for a big snow cat with big power (Torque) Torque is what kills......
Clutches, sprags, planet sets, sun shells, all suffer when they are subjected to big torque...
Another area of issue....Hydraulic leaks in the valve body...Cross leaks at shaft seals and other places....
Poor oil pressure under heavy loads.....Clutches start slipping and it's all over pretty quick....
The engineers design stuff and then use their computers to tell them if the design will work....WRONG ANSWER
Build a test unit and let "Bubba and his brother in law" beat the thing.....When it fails....Figure out why and make it better...Do again.....When Bubba and his Bro have trouble destroying it...You are pretty close......
I have always been fairly civil with my rigs and not flogged things....A have torn up half a dozen 700R boxes behind the anemic 6.2 diesels.....Finally gave up and stuffed in a 400....
Granted...NO OD but the boxes live.......The difference in mileage will never pay for a couple fresh tranny's....Especially when they scatter all over the street..
Enough of my Rant.....Just my thoughts on the subject....
The 700R4 trans is a pretty weak gearbox.....Even the later versions the 4L60E with all the updates and redesigns are still sketchy....
I was in the Auto tranny Bizz for many years and the 700R4 was what paid the bills for us...
They are fine in very light rigs.....Medium sized sedans and small vans.....GM installed them in 1/2 ton pickups and they installed them in the K5 Blazer 4x4 behind the 6.2 Diesel.
The internals are small and way too light for any hard use.....
The later 700R4 right before they renamed them and went electronic were the best of the crop.
The updates, service bulletins and other paperwork from GM was staggering during the early years.
A shelf 8' long stacked like a book shelf was what was needed to hold all the service bulletins and updates...
Yessss...The aftermarket has really stepped up to the bar and fixed a lot of the issues....Still, the components are tiny and you can only do so much with small parts..
IMHO I would use a TH400 BOX and a gear vendors OD behind that......If the rig is a 4x4 it gets a bit tougher to make stuff work due to the space required.
None of the Auto makers made/make a really good tranny... ( Overdrive boxes)
The TH 350 was pretty decent and with a shift kit was good.
The TH 400 was "Nearly bomb proof"
The Ford C6 was a stout box...Again a shift kit was needed to really make them top shelf
The Mopar 727 in stock trim was pretty lame....Shgift kits and a few goodies would get them up to par
Many customers would bitch after we put in a shift kit because of the firm shifts.....
The late Mopar stuff like the 48RFE and 68RFE keep many tranny shops in business....
My son in law has had the tranny in his 08 Dodge 6.7 rebuilt twice now and the cost is staggering.....
Every auto maker wants to brag about their BIG AZZ DIESEL ...But they never think much about the tranny..
The Allison is fairly decent.....Better than the Dodge boxes by light years.
Still I cringe when I think about the power that so many folks are trying to shove at these poor tranny's.....
The older Allison 4 speed boxes are good.....But for most applications they have way too much parasitic drag internally..
A good choice for a big snow cat with big power (Torque) Torque is what kills......
Clutches, sprags, planet sets, sun shells, all suffer when they are subjected to big torque...
Another area of issue....Hydraulic leaks in the valve body...Cross leaks at shaft seals and other places....
Poor oil pressure under heavy loads.....Clutches start slipping and it's all over pretty quick....
The engineers design stuff and then use their computers to tell them if the design will work....WRONG ANSWER
Build a test unit and let "Bubba and his brother in law" beat the thing.....When it fails....Figure out why and make it better...Do again.....When Bubba and his Bro have trouble destroying it...You are pretty close......
I have always been fairly civil with my rigs and not flogged things....A have torn up half a dozen 700R boxes behind the anemic 6.2 diesels.....Finally gave up and stuffed in a 400....
Granted...NO OD but the boxes live.......The difference in mileage will never pay for a couple fresh tranny's....Especially when they scatter all over the street..
Enough of my Rant.....Just my thoughts on the subject....
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Snowy Rivers
Well-known member
UPDATE...UPDATE...More goodies arrived today
The Cloyes timing cover and the crank turning tool that has the place for the degree wheel..
Both of these items are top shelf.....
Adjustable roller bearing cam thrust button.....
Lovely knurled ring to snug up the degree wheel....And a nice set screw to keep the tool from sliding off the crank.
Appears to be that the set screw is metric....Gonna drill it out and tap it 1/4" and use a brass set screw.....
But still...A nice tool.....
The alloy cover is sweet.....Nice finish and a machined spot for the timing mark bracket to bolt into.
The Cloyes timing cover and the crank turning tool that has the place for the degree wheel..
Both of these items are top shelf.....
Adjustable roller bearing cam thrust button.....
Lovely knurled ring to snug up the degree wheel....And a nice set screw to keep the tool from sliding off the crank.
Appears to be that the set screw is metric....Gonna drill it out and tap it 1/4" and use a brass set screw.....
But still...A nice tool.....
The alloy cover is sweet.....Nice finish and a machined spot for the timing mark bracket to bolt into.
Attachments
Not to further hijack your thread. Do you have a suggestion for a better option for a transmission? I need an overdrive automatic with a lockup converter that can be run standalone behind the B3.3. I chose a 700r4 because there seems to be a lot of support like the small block Chevy, its simple to control it and I can get a adapter for the 3.3 to Chevy transmission bell housing and flywheel pattern, The truck will weigh 3500# and the engine will put out 150 hp @ 3000 and 400tq at 1600. I don't have a lot of experience with automatic transmissions. It needs a Chevy pattern and OD with lockup and be able to control it standalone without too much work or $$. its 2 wheel drive and won't tow with it, just a 1/2 ton truck that will be a daily driver that get close to 40 mpg.
Snowy Rivers
Well-known member
No worries on the Hijack......
If it is only light duty......
THE LATEST YEAR OF NON ELECTRONIC 700R
1993 WAS THE ODD YEAR.
Some were electronic some were not...
1990-92 a good bet as these have many factory updates in the design.
To get a 700 to live.
HD OIL PUMP (Front pump) ..... 13 vane pump is a must have.
Replace the sun shell with .....The BEAST Sun shell The factory ones break
The sprags are crap and need upgrading
The input drum (Has many of the clutch packs and the input shaft is pressed into it) An after market hardened steel ring is available that presses over the area of the spline to prevent cracking in the splines.
Unit needs as many clutch plates as can be fitted into each pack.....the 3-4 clutch needs help.
Reverse clutch needs work...
The 2-4 band needs to be upgraded to a much stouter piece.
Low gear in these is 3.06:1 When the shift occurs the band has to grab the drum and stop it to activate 2nd gear
Slippage will make things go away fast.....
Planetaries need upgrading.
There are a multitude of parts that need to be upgraded.
Since I was last through a 700R4 many many changes have been made in the parts available and what works to fix these boxes..
One area that is paramount in the conversion THROTTLE PRESSURE
The cable on the RH front of the box is the "TV" CABLE and must be adjusted properly to maintain the proper oil pressure.
On a factory rig...the adjustments are well documented as to HOW TO DO IT....
On a roll your own it becomes far more interesting and challenging to get the TV set correctly.
Many folks think that this cable is a "Kick down" cable.....Not so....The TV cable must be set properly to achieve the needed pressures to apply the clutches, band and such.
A low TV setting and these boxes will burn up quickly.......
When the electronics came onboard the TV was managed by the electronics......Also the shifts were all handled with solenoids controlled by the electronics......Sensors that monitor the engine load, throttle position, input and output speed sensors.....And on it goes.
My recommendation is a good performance rebuild oriented book on the 700R4 and have a look see at what all you need to do to make these boxes live....
The 700 is not hard to work on......The valve body is the most tedious.. (Not hard...just takes attention to detail)
A good shift kit...I prefer Transgo
A good upgrade on this box with attention to details and it should serve pretty good.....
If it is only light duty......
THE LATEST YEAR OF NON ELECTRONIC 700R
1993 WAS THE ODD YEAR.
Some were electronic some were not...
1990-92 a good bet as these have many factory updates in the design.
To get a 700 to live.
HD OIL PUMP (Front pump) ..... 13 vane pump is a must have.
Replace the sun shell with .....The BEAST Sun shell The factory ones break
The sprags are crap and need upgrading
The input drum (Has many of the clutch packs and the input shaft is pressed into it) An after market hardened steel ring is available that presses over the area of the spline to prevent cracking in the splines.
Unit needs as many clutch plates as can be fitted into each pack.....the 3-4 clutch needs help.
Reverse clutch needs work...
The 2-4 band needs to be upgraded to a much stouter piece.
Low gear in these is 3.06:1 When the shift occurs the band has to grab the drum and stop it to activate 2nd gear
Slippage will make things go away fast.....
Planetaries need upgrading.
There are a multitude of parts that need to be upgraded.
Since I was last through a 700R4 many many changes have been made in the parts available and what works to fix these boxes..
One area that is paramount in the conversion THROTTLE PRESSURE
The cable on the RH front of the box is the "TV" CABLE and must be adjusted properly to maintain the proper oil pressure.
On a factory rig...the adjustments are well documented as to HOW TO DO IT....
On a roll your own it becomes far more interesting and challenging to get the TV set correctly.
Many folks think that this cable is a "Kick down" cable.....Not so....The TV cable must be set properly to achieve the needed pressures to apply the clutches, band and such.
A low TV setting and these boxes will burn up quickly.......
When the electronics came onboard the TV was managed by the electronics......Also the shifts were all handled with solenoids controlled by the electronics......Sensors that monitor the engine load, throttle position, input and output speed sensors.....And on it goes.
My recommendation is a good performance rebuild oriented book on the 700R4 and have a look see at what all you need to do to make these boxes live....
The 700 is not hard to work on......The valve body is the most tedious.. (Not hard...just takes attention to detail)
A good shift kit...I prefer Transgo
A good upgrade on this box with attention to details and it should serve pretty good.....